Mazda 3 Door Light Stays On & Alarm Fix

This is a prevalent issue that most Mazda owners have encountered. Your alarm goes off in the middle of the night. You shut the door hard but the door-ajar light stays on. You can't arm the alarm etc.
The door actuator eventually fails for all doors, it's just a matter of time. In my region, it's a pretty costly part and quite frankly so unnecessary to replace if you follow this method.
I wasn't planning to shoot a how-to video so the details captured wasnt so thorough. This video was initially meant for my personal insta, only later did I realise there was no video at all for a fix.
Kindly drop a comment if you have any concerns or DM.

[@steveandkennyplayguitarsan5107]

Really, really nice video. Thank you! I could not find this video but someone sent it to me. I would advise you to include in title "Mazda 3 Door Light Stays On". Thanks again.

[@Dev4663t]

Heya Steve, glad to be of assistance. Edited the title :)

[@CryptoTVOfficial]

just did this and it worked! cleaned the old grease out and put a little vaseline "petroleum jelly" as grease. remember when you reinstall it all back together to triple check the lock and unlock work before you seal the door up. i put it all back together and the door wasnt locking or unlocking. turns out when i went to seal the actuator back up i didnt align the gears properly. so double check on that and then seal it around with silicone. otherwise this solved my problem!

[@Dev4663t]

yes always best to test the function before assembly. glad its resolved :)

[@alexbrown1995]

Excellent job - well described. Now I can fix the blasted light coming on all the time. Thank you for this, folks.

[@Dev4663t]

glad to help :)

[@lavimelech7617]

Ty

[@appl3turnover]

Thanks, this was very helpful and I used it to get my front passenger door lock actuator working again. Still no problems 2 weeks later.

[@Dev4663t]

Glad it helped Hanna :)

[@klausthefish]

2011 Mazda 3 has a slight different actuator for the lock/unlock rotator. If you have a 2011 you will need to look carefully to slide the arm that is connected to the lock/unlock into the slot. In this video there is a two piece interface so it just goes on without looking. If what I said is confusing this is the arm that is in the middle that rotates when locking and unlocking the sides not push up when pulling the handle. Also be careful with the key actuator arm that is shown in this video pop off the side cover not the end cover as shown. There is a screw holding on the key to the unlock BBM4-59-310E

[@seanlim1985]

nice and detailed.. thanks for posting.

[@Dev4663t]

I dont usually make video unless completely necessary. This was definitely one of them. I found no similar video on teaching people to fix such a simple fault. And i knew it was plaguing almost every mazda 3 owner. So i just had to post it up. Its a lovely car and simple to maintain. A new actuator is simply unneccessary and a waste of money. Glad to help bro 🙏🏽

[@Kiddpr05]

Amazing job. Thnks. I will try

[@Dev4663t]

Give it a go mate. Definitely worth a shot.

[@shetarraprickett9889]

So I have a 2013 Mazda 3 and the door light stays on even when the car is shut off. We hooked up a diagnostics tablet to figure out which door it was and it was the passenger door. We tried to look for a problem but couldn’t find any. Seems to be a grounding problem but I’m not sure. Any way it could be fixed?

[@Dev4663t]

Heya, if i understand the component correctly, it is actually not grounding out which is why the light stays on. It goes off when receives proper ground. Dont quote me on this though. Prior to this fix i was running some test, i attempted to ground one of the wires from the actuator socket, IIRC green and black and the light went off. Again please becareful when doing what i did and double check those wires are not receiving 12v when testing.

[@Electric666s]

How can I tell what door lock sensor is faulty? My car doesn't lock with key fob either, does that indicate it's the drivers door sensor that is faulty?

[@Dev4663t]

Does your model come with a display screen? If it doesnt. Then the only way is to jump the wires on each socket on every door till the door light goes out to test which is faulty. The reason the key fob doesnt lock is because if any of the door is sensed to be open. Automatically disarms the feature to lock.

[@mananjuneja9005]

I'm having issues with the alarm as well. I took the horn fuse out cause it was frustrating but recently my battery died out. I got it replaced cause it was 6 years old. whenever I unlock the or lock using either key or fob, the immobilizer lights start blinking. Could it be possible that it's being triggered randomly overnight ?

[@Dev4663t]

Pretty sure my immo red led light used to blink all the time when its armed or disarm. as long as it goes off while driving and the car starts up fine. your immo is working as it should.

[@adekaik25]

Do you have problem with lock/unlock the door with the key fob button?

[@Dev4663t]

When the door is reading as unlock, you cant arm fob. Other than that my fob has no issues

[@bobsoft]

That's a common problem with the door lock actuator. The motor inside that turns the gear to lock/unlock wears out. Usually the drivers door to go first. If none of the doors will lock with the fob then its a BCM issue

[@alanchappell4845]

I had two problems, one being intermittent passenger door ajar warning and secondly central locking would not lock which happened when a door is recorded as being open due to the faulty brush terminals not contacting or the door actually is open and informing the central computer not to operate the central locking as a door is open. Both of these problems have stopped since cleaning up and bending the brushes down to make better contact which is not too difficult once the 'sealed for life' box is opened and re-sealed with a thin line of super glue. It has been working okay for a while but never know when the fault may return and it is a cheap fix if you don't buy a new actuator lock box.

[@bobsoft]

@@alanchappell4845 That is a proper fix you did. Cleaning with an abrasive, some IPA and then a light coating of dielectric grease before re assembly is what i do. I also replaced the motor (Ali Express) in mine since it was having problems with lock/unlock. I also found out my alarm was going off on sunny days. Turned out to be the hood closed sensor (switch). I disconnected it and then there was no more problems. Until a week later I noticed my battery would run down while the car sat for days. Figured out the computer was constantly sending power to that circuit because it was seeing it open. I soldered the wires together to close that circuit and stop the current draw on my battery.

[@pavelsmetana5133]

Will this repair fix the issue when only door lights are on, but dome (ceiling) light works normally?

[@Dev4663t]

If the door light is coming on when all doors are closed/shut then yes this is the fix

[@pavelsmetana5133]

@@Dev4663t I managed to fix it by repairing the connectors on PCM - they were rusted...

[@bobsoft]

@@pavelsmetana5133 BCM controls the interior

[@AbdullahMuhaymin-cl9wj]

We don't need to clean the yellowish in the actuator thoroughly?

[@Dev4663t]

that yellowing is actually grease taht helps keep the gears lubed. i wouldnt clean it off unless yours is black and grimey. if its clean and yellow, best to leave it as it is

[@Electric666s]

Mycar battery gets drained and door open sensor always on when key is in ignition.. Would they be related.

[@Dev4663t]

Getting drained could be related if your dome lights are on and you leave the car parked for a long time. It could definitely lead to a parasitic draw and kill the battery. But not overnight. Probably weeks.

[@Electric666s]

@@Dev4663t lights out without key in. just wondering if light on could indicate a short somewhere. Also won't lock from fob. will unlock so not fob battery.

[@Dev4663t]

@@Electric666s hard to say mate. Dont quite understand what you mean. If you suspect a short/parasitic drain do the test of using a multimeter and pulling out fuses.

[@Dev4663t]

@@Electric666s ive explained on your other comment why you cant lock. If your door sensor is saying a door is open. Your fob wont lock. You gotta first fix the door issue for the fob to be able to arm your alarm.

[@js6781535]

How did you figure out which door was the issue?

[@Dev4663t]

the display screen on your dash that displays your fuel economy etc, actually shows which door exactly is opening up while driving.

[@bobsoft]

The 1st generation Mazda 3 will not show you which door is open unfortunately.

[@alm7707]

I once did this on my car but the lock was totally different and there is no inside panel so I had to remove the door outer skin which was actually plastic. Wasn't a mazda it was a Smart Car.